Implemented the keyword argument parser.

luprex/core/cpp/luastack.cpp

@@ -3,6 +3,8 @@
 #include <cassert>
 #include <cstdio>
 #include <climits>
+#include "wrap-string.hpp"
+#include "wrap-set.hpp"
 
 LuaSpecial LuaRegistry(LUA_REGISTRYINDEX);
 LuaNilMarker LuaNil;
@@ -76,6 +78,10 @@ lua_State *LuaStack::newstate (lua_Alloc allocf) {
     return L;
 }
 
+void LuaStack::argerr(const char *nm, const char *tp) const {
+    luaL_error(L_, "'%s' should be %s", nm, tp);
+}
+
 bool LuaStack::isinteger(LuaSlot s) const {
     if (lua_type(L_, s) == LUA_TNUMBER) {
         lua_Number result = lua_tonumber(L_, s);
@@ -93,11 +99,12 @@ bool LuaStack::isint(LuaSlot s) const {
 }
 
 bool LuaStack::ckboolean(LuaSlot s) const {
-    luaL_checktype(L_, s, LUA_TBOOLEAN);
+    checkboolean(s, "value");
     return lua_toboolean(L_, s) ? true:false;
 }
 
 lua_Integer LuaStack::ckinteger(LuaSlot s) const {
+    checknumber(s, "value");
     luaL_checktype(L_, s, LUA_TNUMBER);
     lua_Number result = lua_tonumber(L_, s);
     lua_Integer iresult(result);
@@ -109,7 +116,7 @@ lua_Integer LuaStack::ckinteger(LuaSlot s) const {
 }
 
 int LuaStack::ckint(LuaSlot s) const {
-    luaL_checktype(L_, s, LUA_TNUMBER);
+    checknumber(s, "value");
     lua_Number result = lua_tonumber(L_, s);
     int iresult(result);
     if (iresult != result) {
@@ -120,31 +127,31 @@ int LuaStack::ckint(LuaSlot s) const {
 }
 
 lua_Number LuaStack::cknumber(LuaSlot s) const {
-    luaL_checktype(L_, s, LUA_TNUMBER);
+    checknumber(s, "value");
     return lua_tonumber(L_, s);
 }
 
 eng::string LuaStack::ckstring(LuaSlot s) const {
-    luaL_checktype(L_, s, LUA_TSTRING);
+    checkstring(s, "value");
     size_t len;
     const char *str = lua_tolstring(L_, s, &len);
     return eng::string(str, len);
 }
 
 std::string_view LuaStack::ckstringview(LuaSlot s) const {
-    luaL_checktype(L_, s, LUA_TSTRING);
+    checkstring(s, "value");
     size_t len;
     const char *str = lua_tolstring(L_, s, &len);
     return std::string_view(str, len);
 }
 
 lua_State *LuaStack::ckthread(LuaSlot s) const {
-    luaL_checktype(L_, s, LUA_TTHREAD);
+    checkthread(s, "value");
     return lua_tothread(L_, s);
 }
 
 LuaToken LuaStack::cktoken(LuaSlot s) const {
-    luaL_checktype(L_, s, LUA_TLIGHTUSERDATA);
+    checktoken(s, "value");
     return LuaToken(lua_touserdata(L_, s));
 }
 
@@ -457,3 +464,41 @@ bool LuaStack::getvisited(LuaSlot tab) const {
 void LuaStack::setvisited(LuaSlot tab, bool visited) const {
     lua_modflagbits(L_, tab.index(), 0x0010, visited ? 0x0010 : 0);
 }
+
+LuaKeywordParser::LuaKeywordParser(lua_State *L, int slot) {
+    L_ = L;
+    slot_ = slot;
+    if (!lua_istable(L_, slot_)) {
+        luaL_error(L_, "expected an argument which is a table full of keywords");
+    }
+}
+
+bool LuaKeywordParser::parse(LuaSlot out, const char *kw) {
+    lua_pushstring(L_, kw);
+    lua_rawget(L_, slot_);
+    lua_replace(L_, out.index());
+    if (!lua_isnil(L_, out.index())) {
+        parsed_.insert(kw);
+        return true;
+    } else {
+        return false;
+    }
+};
+
+void LuaKeywordParser::check_unparsed_keywords() {
+    if (lua_nkeys(L_, slot_) != int(parsed_.size())) {
+        lua_pushnil(L_);
+        while (lua_next(L_, slot_) != 0) {
+            lua_pop(L_, 1); // Don't need the value.
+            if (!lua_isstring(L_, -1)) {
+                luaL_error(L_, "keyword table contains non-string key");
+            }
+            const char *kw = lua_tostring(L_, -1);
+            if (parsed_.find(kw) == parsed_.end()) {
+                luaL_error(L_, "keyword %s not known", kw);
+            }
+        }
+        assert(false && "should never get here in check_unparsed_keywords");
+    }
+}
+